230 results about "Radiofrequency field" patented technology

A method for the treatment of obesity or other disorders, by wireless electrical activation or inhibition of the sympathetic nervous system. This activation or inhibition can be accomplished by wirelessly stimulating the greater splanchnic nerve or other portion of the sympathetic nervous system using a wireless electrode inductively coupled with a radiofrequency field. The source of radiofrequency energy may be internal or external to the patient. This nerve activation can result in reduced food intake and increased energy expenditure.

A method and apparatus for an ultra-high sensitivity, low cost, passive (no battery) low-power energy harvesting data transmitting circuit energy, such as a RFID (Radio Frequency IDentification) tag integrated circuit “chip.” By using combinations of special purpose design enhancements, the low-power energy harvesting passive data transmitting circuit, such as the RFID tag chip, operates in the sub-microwatt power range. The chip power should be derived from a low-microwatt per square centimeter RF field radiated to the RFID tag antenna from the tag reader (interrogator) or derived from a suitable low signal source, such as a sonic transducer (e.g., a piezoelectric transducer or a low level DC source, such as a bimetallic or chemical source).

An apparatus and method for low frequency asset tracking includes a low frequency transmitter tag associated with a cargo container or other high value commodity, a plurality of receivers that detect low frequency signals, and a microprocessor that uses algorithms and / or data pertaining to the propagation characteristics of the signal to locate the position of the container or high value commodity. The tag may include sensors to monitor container properties or conditions, such as temperature, motion, intrusion, RF fields, or other properties of interest. Sensor data may be modulated on the low frequency transmitter signal.

An imbalanced radio frequency (RF) field creates a retarding barrier near the exit aperture of a multipole ion guide, in combination with the extracting DC field such that the barrier provides an m / z dependent cut of ion sampling. Contrary to the prior art, the mass dependent sampling provides a well-conditioned ion beam suitable for other mass spectrometric devices. The mass selective sampling is suggested for improving duty cycle of o-TOF MS, for injecting ions into a multi-reflecting TOF MS in a zoom mode, for parallel MS-MS analysis in a trap-TOF MS, as well as for moderate mass filtering in fragmentation cells and ion reactors. With the aid of resonant excitation, the mass selective ion sampling is suggested for mass analysis.

Ion manipulation systems include ion repulsion by an RF field penetrating through a mesh. Another comprises trapping ions in a symmetric RF field around a mesh. The system uses macroscopic parts, or readily available fine meshes, or miniaturized devices made by MEMS, or flexible PCB methods. One application is ion transfer from gaseous ion sources with focusing at intermediate and elevated gas pressures. Another application is the formation of pulsed ion packets for TOF MS within trap array. Such trapping is preferably accompanied by pulsed switching of RF field and by gas pulses, preferably formed by pulsed vapor desorption. Ion guidance, ion flow manipulation, trapping, preparation of pulsed ion packets, confining ions during fragmentation or exposure to ion to particle reactions and for mass separation are disclosed. Ion chromatography employs an ion passage within a gas flow and through a set of multiple traps with a mass dependent well depth.

The ion acceleration system or complex (T) for medical and / or other applications is composed in essence by an ion source (1), a pre-accelerator (3) and one or more linear accelerators or linacs (6, 8, 10, 13), at least one of which is mounted on a rotating mechanical gantry-like structure (17). The isocentrical gantry (17) is equipped with a beam delivery system, which can be either ‘active’ or ‘passive’, for medical and / or other applications. The ion source (1) and the pre-accelerator (3) can be either installed on the floor, which is connected with the gantry basement, or mounted, fully or partially, on the rotating mechanical structure (17). The output beam can vary in energy and intensity pulse-by-pulse by adjusting the radio-frequency field in the accelerating modules of the linac(s) and the beam parameters at the input of the linear accelerators.

A combination of specific antenna type(s), with a system of specific antenna Rf field deployment, combined with the intelligent sensing of differing micro processor control of a digital antenna attenuator that controls disproportional attenuation (either synchronously or independently) of the transmission and reception areas of the antenna(e), of electronically paired devices, together with conditional time delays, is used to securely determine the ID and intent of an Rf access system user. A multifunctional remote device (condition unit) is carried by a carrier, the remote device transmits a short range radio frequency (Rf) signal which, when within range, is received by a stationary control unit. A second multifunctional remote device (cluster unit) is carried by the operator of the carrier and must be in secure communication with the condition unit to enable secure transmission between the control and the control unit. The operation of both said multifunctional remote units changes significantly with application in differing fields of use. By intelligently varying the interactive antenna Tx and Rx area, the proximity and therefore position of the remote (condition) unit to the base (control) unit can be deduced, outwardly appearing as a decoding of the intent of the carrier. This system can be implemented as a secure card-less RFID entry system for vehicle, building, border entry and mass transit systems.

A radio frequency transmitter arrangement for a magnetic resonance apparatus has a distribution unit and an antenna unit, wherein the antenna unit, to generate radio frequency fields, is fashioned in at least two orthogonal modes, and the distribution unit is fashioned for the division of an RF transmission signal into at least two mode feed signals. At least one adjustment unit is provided to adjust the amplitude and / or phase of one of the mode feed signals and is connected with the antenna unit such that each of the mode feed signals generates a radio frequency field in one of the modes. A multiple transmitter arrangement has at least two radio frequency transmitter arrangements and at least two 180° hybrids. A method is provided to determine at least one setting parameter of the adjustment unit.

A system for controlling an implantable medical device (e.g., a drug delivery device) susceptible to malfunctioning during exposure to a magnetic field and / or Radio Frequency field (e.g., during a magnetic resonance imaging procedure) and a method for operating the same. Exposure of the implantable device to the magnetic field and / or the Radio Frequency field is detected using the sensing device. When the detected magnetic field and / or Radio Frequency field exceeds a corresponding predetermined threshold level, an input signal is generated at the microcontroller. In response to the generated input signal, the microcontroller automatically triggers (i) a safety mode enabling a predetermined safety mode operation that alters some operation, without ceasing all operation, of the implantable medical device and / or (ii) after expiration of a predetermined safety mode time interval when the at least one field being detected falls below its corresponding predetermined threshold level or a predetermined period of time elapses, a self testing mode enabling a predetermined self testing operation to verify proper operation of the implantable medical device. Preferably, both the safety and self testing modes are automatically triggered.

A time-variable magnetic fields generator for a magnetic resonance apparatus has at least one gradient coil with conductors extending essentially in the region of a subject-receiving hollow opening of the magnetic resonance apparatus, and that is free of conductors in a middle axial region of the hollow opening, a first radio-frequency shield that encloses the conductors disposed on the one side of the middle region, a second radio-frequency shield that encloses the conductors disposed on the other side of the middle region, a radio-frequency antenna element that emits a radio-frequency field, disposed between the first and second radio-frequency shield in the middle region, a third radio-frequency shield proceeding radially, externally around the antenna element, such that the radio-frequency shields delimit a field return space within the generator and that is designed for a return of the radio-frequency field.

In a method and device for monitoring the physiologically effective radio-frequency exposure in at least one specific volume region of an examination subject in a magnetic resonance data acquisition scan in a magnetic resonance system, the magnetic resonance system having a radio-frequency antenna structure with a number of individually controllable radio-frequency signal channels for generation of radio-frequency field distributions in an examination volume including the examination subject, amplitude values are acquired that respectively represent, at specific acquisition points in time, a signal amplitude of the radio-frequency signals emitted or to be emitted via the radio-frequency signal channels in the course of the magnetic resonance measurement. Also, phase values are acquired that represent the phases of the appertaining radio-frequency signals at these points in time. Local exposure values are then determined on the basis of the amplitude values and phase values, these local exposure values respectively representing a physiological exposure that the radio-frequency pulses cause at the examination subject at a specific location at a specific time. Based on this, exposure control values are determined that are compared with predetermined exposure limit values. When an exposure limit values is reached or exceeded, a control signal is output.

In a wireless network comprising access points deployed within a designated zone of coverage, the radio frequency field strength resulting from radiation from the access points is optimised as a function of location by means of control of the transmission power and / or radiation pattern of the access points in response to measurements from sensors at defined locations that measure received signal power, the received power being related to radio frequency field strength. Sensors may be deployed within the designated zone of coverage, at the edge of the zone and / or outside the zone and optimisation of the transmission parameters of the access points in terms of transmission power and / or radiation pattern is carried out taking into account the location of the sensors in addition to the received power at the sensors.

The present invention relates to an improved ion mobility spectrometer and method for the analysis of chemical samples. The improvements are realized in the optimization of resolution and sensitivity. Increases in sensitivity are realized by preserving a narrow spatial distribution of migrating ions through the use of periodic / hyperbolic field focusing. Use of a plurality of drift cells and a new RF field focusing interface are discussed.

The present invention discloses a portable magnetic resonance method and device for tissue analysis including a magnetic field generator, a radio frequency source, a radio frequency detector, a power source, and a processor configured for receiving radio frequency signals and for analyzing those signals to determine discriminatory tissue characteristics in a planar section of a region of interest within a patient's body, with the magnetic field generator positioned outside of the patient's body, and more preferably hand held in proximity to the patient's body. The processor is configured to direct the radio frequency source to produce a radio frequency field in varying planar sections of the region of interest at Larmor frequencies such that spins resonant with the Larmor frequency in the particular planar section of the region of interest are excited. The processor is further configured to direct the radio frequency detector to receive magnetic resonance signals produced in each planar section of the region of interest in response to the applied radio frequency field, to compute from the acquired magnetic resonance signals a quantitative metric indicative of discriminatory characteristics of differing tissues or other materials within each such planar section, and to produce human discernable output indicative of such quantitative metric.

The invention provides a communication system capable of automatically selecting an NFC simulation card. The communication system comprises an NFC card reader and electronic equipment with an NFC function. The NFC card reader detects an NFC radio frequency field of the electronic equipment, sends third query information, wherein the third query information comprises first identification information and the supported service type of the simulation card; the electronic equipment determines whether a first analog card corresponding to the first identification information exists or not; when it isdetermined that the first simulation card exists, the electronic equipment determines whether a second simulation card corresponding to the service type exists or not; when it is determined that thesecond simulation card exists, the electronic equipment sends fourth response information, and the fourth response information carries second identification information; the NFC card reader sends cardselection instruction information; and the electronic equipment receives the card selection instruction information and sends card selection response information. According to the technical scheme, the electronic equipment can automatically select the corresponding analog card, so that the NFC payment efficiency is improved.

Disclosed is an apparatus capable of hosting a secure module. The apparatus comprises a communication unit capable of near field communications, and a control unit configured to co-operate with the secure module. The control unit is further configured to detect a radio frequency field and, in response to the detection of the radio frequency field, to pass, to the secure module, control of establishing a near field connection through the communication unit. Also disclosed is a secure module, comprising a control unit configured to assume control of establishing a near field connection, wherein the control unit is further configured to provide, in the course of the near field connection establishment, a set of capabilities comprising near field communication capabilities of the secure module and near field communication capabilities of an apparatus hosting the secure module.

A system for detection and tracking of objects which carry low radio frequency tags that comprise an inductive antenna and transceiver operable at a first radio frequency below 1 megahertz, a transceiver operatively connected to that antenna, an ID data storage device, a microprocessor for handling data from the transceiver and data store, and a tag energization inductive antenna which can receive radio frequency energy from an ambient radio frequency field of a second low radio frequency. The system includes a field communication inductive antenna disposed, preferably at a distance of several feet from each object, that permits effective communication therewith at the aforesaid first radio frequency, a data receiver, transmitter and reader data processor in operative communication with the field communication inductive antenna, and a field energization inductive antenna which can produce the ambient radio frequency field at the tag energization inductive antenna.

A radio frequency transmitter arrangement for a magnetic resonance apparatus has a distribution unit and an antenna unit, wherein the antenna unit, to generate radio frequency fields, is fashioned in at least two orthogonal modes, and the distribution unit is fashioned for the division of an RF transmission signal into at least two mode feed signals. At least one adjustment unit is provided to adjust the amplitude and / or phase of one of the mode feed signals and is connected with the antenna unit such that each of the mode feed signals generates a radio frequency field in one of the modes. A multiple transmitter arrangement has at least two radio frequency transmitter arrangements and at least two 180° hybrids. A method is provided to determine at least one setting parameter of the adjustment unit.

This invention provides one high voltage transducer power unit, which comprises shell, function parts, control board, capacitor array and dissipation part, wherein, capacitor array is put on unit bottom; dissipation device is distributed on one side of capacitor array and other side with control board; there is shield board between control board and power parts with power parts on dissipation surface to connect parts through copper band.

An item price notification system automatically interrogates product labels to determine product, pricing, and other unique data. The system uses a radio frequency (RF) radio frequency transceiver to generate an RF field to communicate with radio frequency identification (radio frequency transponders) transponders mountable to product display shelves. The radio frequency transponders contain information such as pricing information, nutritional information, and other unique data about the various products. As the RF radio frequency transceiver moves into proximity to various radio frequency transponders for a variety of products, the unique data are received by the RF radio frequency transceiver and are displayed for the user. The displayed data allows a user to make comparisons between products, and the system display and memory allow a user to store the unique data for those products and to make instant and cumulative product, price, and other comparisons.

The invention relates to treatment of solid cancers and more particularly to a method and apparatus correlating proton beam intensity with proton delivery efficiency, optionally in a raster beam scanning system. The system induces betatron oscillation on the proton beam causing the beam to traverse an extraction material resulting in slowed protons and a feedback current proportional to the proton flux. A controller receives the desired intensity from an irradiation plan and the feedback current and adjusts the radio-frequency field in the radio-frequency cavity system to yield an intensity of the proton beam that matches the desired intensity from the irradiation plan. Preferably, the intensity of the proton beam correlates with radiation delivery efficiency. The system preferably operates in conjunction with a multi-field charged particle cancer therapy system, with charged particle beam injection, particle beam acceleration, multi-axis charged particle beam control, and / or targeting methods and apparatus.

In a method and magnetic resonance apparatus for compensation of contrast inhomogeneities in magnetic resonance images caused by spatial distributions of the radio frequency field associated with the radio frequency pulses that are emitted in order to acquire magnetic resonance (MR) data, multiple individual MR images of a particular region of a subject are recorded with different radio frequency pulse sequences leading to different flip angles. A common contrast-homogenized image for the affected region then is generated based on the different individual images, so that within the contrast-homogenized image, intensity variations due to a distribution of the flip angle are smaller than in the individual images, at least in some areas.

A local coil unit for a magnetic resonance apparatus, which radiates a radio-frequency field into an examination subject, has a housing and at least a part of the housing is formed of an insulating dielectric material that passively compensates for an inhomogeneity in the high-frequency field in the subject. The material has a relative dielectric value εr of greater than 50, preferably greater than 100, and a dielectric loss factor tan δ of less than 2.5×10−2, preferably less than 1×10−3. In the dielectric material displacement currents are generated which create an additional magnetic field that compensates for the minima in the B1 field as a result of the eddy currents arising in the patient due to the radio-frequency radiation.

A glass-coated article having substantially rectangular cross-section is excited using a tickler magnetic field. Harmonics of the a.c. magnetic field that are thusly caused to emanate from said article are detected by either magnetic field sensing coils or by mixing with a propagating radio frequency field. A portal design ensures the detection of the glass-coated article having substantially rectangular cross-section, no matter its spatial orientation. Teachings of the instant invention are critical for the use of glass-coated articles having substantially rectangular cross-section in a number of applications that include but are not limited to anti-theft systems; monitoring of tamper-proof packages; tracking, tracing and identification of currency, secure documents, drivers licenses, and passports; tracking of personnel, labels and paper products, merchandising items, and composites; monitoring movement of textiles including clothing and garments and materials used to make said textiles containing the invention; authentication and brand theft protection, credit card verification and protection against fraud; biometrics and other medical applications.